Key parameters at a glance

A radius of 5.07 Earth radii
A mass of 22.60 Earth masses
Surface gravity around 0.88 g
An orbital period of 3.855 days
Semi-major axis 0.0402 AU
Equilibrium temperature 714 K (441 °C)
Distance from Earth 434.19 light-years
Earth Similarity Index 0.263
Travel time at Voyager 1 speed 7,656,859 years
Almost certainly tidally locked to its host star given the close orbit

TOI-6223 b Planet Profile

Physical Specs

Radius

5.07 R⊕

Radius (Jupiter)

0.452 R♃

Mass

22.60 M⊕

Mass (Jupiter)

0.071 M♃

Density

0.95 g/cm³

Surface Gravity

0.88 g (Earth)

Classification

Planet Type

Neptune-like

ESI Score 0.263

HZ Position Inner

Controversial No

Discovery

Year 2025

Method Transit

Facility Transiting Exoplanet Survey Satellite (TESS)

Telescope 0.1 m TESS Telescope

Size rank in cohort

Rank by radius

#374of 574

top 65.0%

This planet

5.07R⊕

Neptune-like median

6.39R⊕

Nearest-size peers

K2-98 b 5.07 R⊕ V1298 Tau c 5.08 R⊕ Kepler-19 d 5.06 R⊕

Metric	Earth	TOI-6223 b	Jupiter
Radius (R⊕)	1.00	5.07	11.21
Mass (M⊕)	1.00	22.60	317.83
Density (g/cm³)	5.51	0.95	1.33
Surface Gravity (g)	1.00	0.88	2.53
Insolation (S⊕)	1.00	41.86	0.037

Star Catalogue Identifiers

TIC

TIC 288144647

Gaia DR2

Gaia DR2 2872039996566868480

Gaia DR3

Gaia DR3 2872039996566868480

System

TOI-6223

Percentile among Neptune-like cohort

Radius 5.070 R⊕ · percentile 35 / cohort 574

Mass 22.600 M⊕ · percentile 37 / cohort 574

Orbital period 3.86 d · percentile 11 / cohort 524

Distance 133.12 pc · percentile 30 / cohort 572

ESI 0.263 · percentile 41 / cohort 574

Orbit & Habitability

Orbital Dynamics

Period

3.855 days

Semi-major axis

0.0402 AU

Eccentricity

—

Inclination

88.68 °

Year Length

A year here lasts approximately 3.86 Earth days (1.1% of a terrestrial year) at a mean orbital distance of 0.0402 AU.

Transit Fingerprint

Depth

0.662 %

Duration

2.014 h

Impact parameter b

0.345

Rp / R★

0.080650

Transit midpoint (BJD)

2,459,856.4888

Photometric dip

Transit produces a flux drop of 6,624 ppm lasting ≈ 2.01 h.

Extended Orbital Architecture

Planet / star radius ratio

0.080650

Semi-major axis / stellar radius

14.990

Impact parameter (b)

0.345

Transit mid-time (BJD)

2,459,856.4888

Angular separation (arcsec)

0.30200

Eq. Temperature

714K

(441 °C)

Insolation (S⊕)

41.86

Earth = 1.00

Earth Similarity (ESI)

0.263

0 = alien, 1 = Earth-identical

Inside the inner HZ boundary (too hot for liquid water) — the surface is too hot to retain surface water. Close-orbiting tidally-locked around a cool host.

Discovery Paper

Primary reference

Yalcinkaya et al. 2025

Instrument

TESS CCD Array

Publication

2025-10

Observation locale

Space

Discovery cohort

Planets confirmed in 2025 at Transiting Exoplanet Survey Satellite (TESS) (12 shown).

TOI-1266 d · Super-Earth TOI-2267 c · Rocky Terrestrial TOI-5799 c · Super-Earth TOI-5728 b · Super-Earth TOI-5716 b · Rocky Terrestrial TOI-7166 b · Sub-Neptune TOI-2267 b · Rocky Terrestrial TOI-2093 c · Sub-Neptune TOI-2267 d · Super-Earth TOI-5489 c · Super-Earth TOI-1743 b · Super-Earth TOI-4364 b · Sub-Neptune

Host System: TOI-6223

Spectral Class

M-type red dwarf

Effective Temperature

3,895 K — cooler than the Sun (5,778 K)

Estimated Age

9.80 Gyr — older than the Sun (4.6 Gyr)

Stellar Radius

0.576 R☉

Stellar Mass

0.582 M☉

Metallicity [Fe/H]

-0.12

Extended Stellar Properties

Surface gravity (log g)

4.682 dex

Stellar density

4.290 g/cm³

Metallicity ratio

[Fe/H]

Distance

133.12 parsec

Light-years 434.19 ly

V-band magnitude

14.22 mag

Voyager-speed travel 7,656,859 yr

Multi-band Host Photometry — 11 bands

Astrometric Data

Parallax

7.483 mas

Total Proper Motion

32.497 mas/yr

PM Right Ascension

14.05 mas/yr

PM Declination

-29.30 mas/yr

Galactic Cartesian (pc)

x = 0.836 · y = -0.059 · z = 0.546

Equatorial (J2000)

RA 355.95060° · Dec 33.06724°

Galactic ℓ, b

106.953° · -27.697°

Ecliptic λ, β

11.013° · 31.610°

HTM-20 index

-345037585